Irradiance prepass, light cache, and glossy rays.

[pjkw]

The new animation prepass mode for irradiance map is much welcomed by me. However Im a bit confused how it works with light cache and glossy rays.

Im using irradiance map for primary bounces, and irradiance map for 2ndary, do I need to have 2ndary bounces on for both the prepass render and the beauty render? It seems I get the same light if I turn 2ndary bounces off in the beauty render but the rendertimes become ALOT longer.
Im guessing this is because the glossy rays aren't based off the light cache anymore..?
Is there something Im missing that would let me do the light cache pass just once?

Also, im wondering what settings effect the glossy rays when I use light cache for glossy rays, Im currently having flicker in glossy refractions I can't seem to get rid of, is it just the light cache subdivs or do refraction subdivs in the material still affect?

[vlado]

Unless you had the option "Use light cache for glossy rays" when you calculated the irradiance map, you do not need the light cache once the irradiance map is already calculated.

For the flickering, it is probably caused by the light cache which is calculated for each frame. Maybe would be better to turn off the "use light cache for glossy rays" option and leave it to the smooth irradiance map instead. It will be slower though.

In general, it is possible to generalize the light cache for animation in the same way as the irradiance map, but I don't know how useful this will be... otherwise, for reducing flickering in the light cache, try more subdivs, larger filter size, and possibly the "Fixed" filter.

Best regards,
Vlado

[pjkw]

Doing these renders now, Ive rendered with glossy rays checked and Ive had the same subdivs on lightcache for both the prepass and the actual renderpass.. what effect will this give? Will the prepass lightcache be responsible for the GI and the renderpass for the glossy effects... or what? I feel a bit stupid doing the calculations twice and If I were to up the subdivs I really wouldnt want to do this on both the prepass and the renderpass.

[Guest]

How come the light cache has to be calculate twice if use for glossy rays is on?